Now to the crisis in the middle east. The dramatic escalation of the ground war in gaza. 60 Palestinians reported dead. Tens of thousands seeking refuge with the U.N. More Israeli soldiers reported killed. Alex Marquardt is in gaza. Good morning, Alex. Reporter: Good morning, George. Today is the deadliest day yet. And it's still early. The shelling by Israeli forces in eastern gaza so bloody that Israel and hamas agreed to a two-hour cease-fire to evacuate the dead and wounded. But in under an hour, it was broken. Now the fighting continues. The booms of Israeli artillery raining down this morning on eastern gaza. Tank shells are landing every few seconds. People are streaming out of this neighborhood. You can see the looks of terror on their faces. They don't have anywhere to go. They're getting in any car they can to get out of here. I don't know where I'm going, this woman told me. All we have is this white flag. Fleeing on foot with his family, this young man said they left the dead and wounded behind. Inside, scenes of carnage. Mangled bodies lying in the streets. At least 60 killed. Gaza's death toll now over 400. Around 100 are children. This morning, it is nothing short of a massacre. A deliberate massacre. War crimes committed daily. Now there's a deliberate shelling and bombing and destruction of whole areas. Reporter: Hamas has continued to fire rockets into Israel from residential areas. Warning sirens going off across the country. People running for shelter. Two Israeli civilians have been killed so far. Many of the rockets intercepted by the iron dome missile shield. Palestinian militants have stepped up assaults. A number of Israeli soldiers have been killed and wounded. New reports of several this morning. Israel says the offensive's main goal is to take out the vast network of hamas tunnels. That militants have used repeatedly in recent days to infiltrate Israel. The Israeli plan is not to occupy gaza or destroy hamas but to weaken them. And as the civilian death toll grows here, the big question is at what cost? International pressure is growing on both sides to end this now 13-day conflict. Israel and hamas have been talking through intermediaries. But so far, neither side showing any signs of backing down.

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